1. Field of the Invention
Embodiments of the present invention generally relate to musical tone signal processing systems and methods, and, in specific embodiments, to musical tone signal processing systems and methods for expanding and contracting an acoustic image.
2. Related Art
According to the apparatus cited in Japanese Laid-Open Patent Application Publication (Kokai) Number 2000-504526), sorts a monaural signal to the left and the right in accordance with frequency bands. This apparatus allows the output to have a simulated stereo sound.
According to the sound effect imparting apparatus cited in Japanese Laid-Open Patent Application Publication (Kokai) Number 08-123410) can provide an expansive feeling to the sound of each sound source that is configured by left and right channels. With that kind of sound effect imparting apparatus, specifically, the sound is made to have an expansive feeling by blurring the discrimination of the localization of the sound by adjusting the localization and inverting the phase of the timbre data of each frequency band by time division to each of the left and right channels in each of the frequency bands. However, for both apparatuses, it is difficult to expand the acoustic image of the input sound source freely in conformance with one's desires.